Position Angle Research Articles

Comparative effectiveness of the exact versus estimated angle of head position in the Epley maneuver: a randomized controlled trial.

Introduction The Epley maneuver is the recommended treatment for benign paroxysmal positional vertigo of the posterior semicircular canal (PC-BPPV). Traditionally, the angle of the patient's head in each position during the Epley maneuver is not monitored and subjectively estimated by physicians. As a result, deviations of head angles from the standard may affect the treatment result. This study aimed to compare the outcome of the Epley maneuver between the group of exact head angles and the group of subjectively estimated angles (traditional Epley maneuver). Methods A single-blind randomized controlled trial was conducted at the Department of Otolaryngology, Chiang Mai University Hospital. PC-BPPV patients were attached with the head angle measuring device and randomized into 2 groups: Group I - the exact angle group, physicians performed the Epley maneuver with accurate head angle in each step; and Group II - the estimated angle group, physicians performed the Epley maneuver by estimating the head angle (traditional Epley maneuver). The treatment outcomes were measured at 1 week in the aspects of negative Dix Hallpike results and severity of dizziness. Results Thirty-one PC-BPPV patients were recruited and randomized into Group I (15 participants) and Group II (16 participants). Both groups showed clinical improvement. Although significant deviations of head angles were observed in group II, there was no significant difference in outcomes between the two groups in terms of negative Dix Hallpike and severity of dizziness at the 1-week follow-up. Conclusion Although significant variations of head angles were observed during the traditional Epley maneuver by experienced physicians, these deviations were slight (less than 15°) and did not significantly affect the successful treatment outcome at 1 week, in terms of negative Dix Hallpike and severity of dizziness, when compared to the group with accurate head angle during the Epley maneuver.

Evaluating the impact of soft bracing and textile engineering in enhancing postural control and proprioception in adolescent idiopathic scoliosis

Adolescent idiopathic scoliosis (AIS) is often associated with unbalanced posture and proprioceptive deficits and is particularly prone to progression during puberty. However, limited research has addressed early intervention for mild curves (10-20 degrees). This study aims to examine the effects of a soft bracing intervention using the Posture Correction Girdle (PCG) on 3D postural balance and proprioception in adolescents with early-stage scoliosis. Cobb angles were measured with the X-ray Imaging before and after a 2-h wear trial with the girdle to assess immediate curve reduction. Postural angles were visualized using 3D body scanning. Proprioception was assessed using a motion capture system, focusing on trunk, neck, elbow, and knee movements under the eye-open and eye-closed condition. Data were analyzed using descriptive statistics, t-tests, and Pearson’s correlation and partial Mantel tests to examine postural balance and proprioceptive outcomes. Results indicated significant improvements in postural balance in the frontal and sagittal planes, and proprioception in the dominant-side elbow. However, other proprioceptive measures showed limited changes, with responses differing by spinal curvature. Strong correlations emerged between proprioceptive function and postural angles in the thoracic and lumbar regions. These findings suggest that soft bracing can enhance postural control for mild AIS, though individual variability in responses highlights the need for personalized bracing strategies. This study supports soft bracing as a promising therapeutic option, underscoring the importance of individualized assessment to optimize brace design and effectiveness in early-onset scoliosis management.

Quaternion-Based Fast SMC–PD Cross-Domain Tracking Control for Coaxial Hybrid Aerial–Underwater Vehicle Under Oceanic Disturbances

In this study, nonsingular modeling and cross-domain trajectory tracking control problems for a special class of coaxial hybrid aerial–underwater vehicles (HAUVs) are investigated. Coaxial HAUVs need to effectively overcome the influence of hydrodynamic factors when moving underwater, so the attitude angle required by coaxial HAUVs is much larger than that in the air. The attitude representation based on quaternion modeling is adopted to avoid the inherent singularity of Euler angle modeling. A cascade sliding mode control and proportion differentiation (SMC-PD) controller is proposed, which is used to position trajectory and attitude quaternion tracking control, respectively. An adaptive sliding mode controller based on disturbance observer (DO) enhancement is adopted in the outer loop to carry trajectory tracking control. At the same time, the expected attitude angle is calculated by the outer loop (position) and is converted into the expected quaternion. With reference to the idea of enhanced robustness in active disturbance rejection control (ADRC), a feedforward proportion derivation (PD) controller based on DO enhancement is used to track the desired quaternion. A variable parameter adaptive algorithm based on the learning rate is introduced in the cascaded SMC-PD controller. The error convergence speed of the system is further improved by adaptively changing the controller parameters. The stability of the proposed control scheme is proved by using the Lyapunov theory. The numerical simulation results show that the controller has good robustness and effectiveness.

Determining the stability of a fire truck tanker against overturning while driving through crossed forest terrain

The object of this study is to consider dynamic processes in the tank of a fire truck with different levels of water filling. The task to be solved is to determine the data on the fluctuation of the center of mass of a dynamic system, which consists of the water tank of a fire truck tanker truck, when it moves through rough forest terrain at different speeds. The data make it possible to predict the danger of a fire truck tipping over. In the process of solving the task, an estimation model of a fire truck tanker truck was built together with a water tank, using the LS-Dyna dynamic systems simulation software package. In order to reproduce the dynamic impact on the fire truck tanker with the water capacity exerted by the relief of the rugged forest area, the time dependences of the angles of current position of the fire truck tanker – roll angle, yaw, and pitch – were established. The resulting dependences were used as boundary conditions to reproduce the dynamic influence of the terrain. The turning angles of the water tank of a fire truck were determined depending on the unevenness of the terrain, the geometry of which was calculated by a pseudo-random number generator. Using the explicit method for integrating the dynamics equations, implemented in the code of the LS-Dyna software package, the patterns of fluctuations of the center of mass of the water tank of the fire truck tanker depending on the level of filling and speed of movement were defined. Using results from the mathematical modeling of dynamic processes in the fire truck tanker, a numerical algorithm was developed for this fire truck tanker to maintain its stability against overturning. Therefore, the results of this study have a direct practical application in the field of fire truck tanker design safety and could be used to improve and devise new technologies in this field

Research on Response Postures of Subway Train in Straight Line Collision

A six-car subway train finite element model was developed to investigate possible response postures under impact accidents. Considering the plastic deformation of carriages and weak points of the train front, the simulation included two conditions: train–train collision and collision with an obstacle. Comprehensive response postures were obtained. A one-dimensional dynamic theory model was established to verify the rationality of the FEM model. The influence of impact speed, impact angle, and impact position on the energy consumption and response postures were discussed. The results show that one accident condition is accompanied by a variety of response postures. The main factors of climbing are asynchronism of yaw and pitch motions of adjacent carriages and plastic deformation of carriage ends, which leads to vertical arch. In oblique and front-side collision, the lateral force and the deviation of train front cause rapid derailment, and large lateral movement of the front and lateral buckling happen subsequently.

Precise Measurements of the LMC Bar’s Geometry with Gaia DR3 and a Novel Solution to Crowding-induced Incompleteness in Star Counting

Abstract We present new measurements of the 2D geometry of the LMC’s stellar bar with precise astrometric observations of red clump stars in Gaia DR3. We develop a novel solution to tackle crowding-induced incompleteness in Gaia data sets with the Gaia BP-RP color excess. Utilizing the color excess information, we derive a 2D completeness map of the LMC’s disk. We find that incompleteness biases the bar measurements and induces large uncertainties. With the completeness-corrected 2D red clump map, we precisely measure the LMC bar’s properties using Fourier decomposition. The bar radius (semimajor axis) is R bar = 2.13 − 0.04 + 0.03 kpc, and its position angle is 121.°26 ± 0.°21. The bar’s strength as quantified by the Fourier bi-symmetric amplitude is S bar = 0.27, indicating that the LMC has a significant bar perturbation. We find the bar has an axis ratio of 0.54 ± 0.03, and is offset with respect to the center of the outer disk isophote at R ≈ 5 kpc by 0.76 ± 0.01 kpc. These LMC bar properties agree with a hydrodynamic model where the SMC has undergone a recent direct collision with the LMC. We compare the LMC’s bar properties with other barred galaxies in the local Universe, and discover that the LMC is similar to other barred galaxies in terms of bar-galaxy scaling relations. We discuss how our completeness correction framework can be applied to other systems in the Local Group.

Parameterized ZNCC image correlation for rotary-angle measurement

Abstract High-accuracy rotary-angle measurement is critical for precise positioning and control of robots, machine arms, and machine tools in industry. Image-based measurement is a very promising technology for angle positioning owing to its simple system, low cost, and good robustness to environments. Image correlation, such as the zero-mean normalized cross correlation (ZNCC) method, can obtain high accuracy image-positioning results, but their efficiency is too low to directly use in industries. This paper proposes to measure the absolute rotary angle using a parameterized ZNCC (PZNCC) image correlation method. The PZNCC expresses the ZNCC coefficient by the image shift parameters explicitly, so that the precise-match point corresponding to the global ZNCC maximum can be efficiently obtained and no image-resampling process is required. As a result, PZNCC is approximately 5 times faster than the classic inverse compositional Gauss–Newton (IC-GN) algorithm. Experiments show that rotary angle measurement based on PZNCC can obtain absolute angle positions with an accuracy of 1.16 arcsec (RMSE).

Preview-Based Optimal Control for Trajectory Tracking of Fully-Actuated Marine Vessels

In this paper, the problem of preview optimal control for second-order nonlinear systems for marine vessels is discussed on a fully actuated dynamic model. First, starting from a kinematic and dynamic model of a three-degrees-of-freedom (DOF) marine vessel, we derive a fully actuated second-order dynamic model that involves only the ship’s position and yaw angle. Subsequently, through the higher-order systems methodology, the nonlinear terms in the system were eliminated, transforming the system into a one-order parameterized linear system. Next, we designed an internal model compensator for the reference signal and constructed a new augmented error system based on this compensator. Then, using optimal control theory, we designed the optimal preview controller for the parameterized linear system and the corresponding feedback parameter matrices, which led to the preview controller for the original second-order nonlinear system. Finally, a numerical simulation indicates that the controller designed in this paper is highly effective.

Systemic Effects of Molar and Incisor Biting on Walking Direction With and Without Visual Feedback

Gait stability and walking direction control are conventionally attributed to coordination among somatosensory, visual, and vestibular systems. Recent evidence of functional interdependence between masticatory and neuromuscular systems indicates that the stomatognathic system is neurologically integrated with various body systems relevant to movement planning and execution. This study investigated the effects of unilateral molar biting and incisor biting on walking with and without visual feedback. A cohort of 31 healthy young adults aged 21 to 30 years (average age of 23.93 ± 1.89) participated in this study. Three types of errors in walking direction (angle error, position error, and curve error) were computed. Our findings indicate that, in right-handed individuals, irrespective of visual feedback, unilateral biting caused systematic deviations toward the biting side from initiation to termination of walking. The consistent deviation in walking, particularly during unilateral right biting conditions in right-handed individuals, may indicate a complex interplay between masticatory function and gait control mechanism, potentially influenced by handedness and motor lateralization within the cortex. This study establishes a foundation for future research exploring the interrelation between bite location, visual feedback, and motor control in diverse populations. This research may provide insight for more efficient interventions for gait-related disorders.

I-f Control Method for SynRMs Uses Simple Inductance Identification and Voltage Injection for Current and Angle Control.

The sensorless vector control method of synchronous reluctance motors (SynRMs), based on extended back electromotive force (EMF) or flux observation, has been widely applied in the medium- or high-speed range. However, in the low-speed and low-current range, the extended back-EMF and flux are nearly zero. The use of the current frequency (I-f) control method can enable the motor to pass through the low-speed region, thereby ensuring that the back-EMF and flux reach a large value. I-f control methods that are widely used in permanent magnet synchronous motors (PMSMs) may encounter many problems when applied to SynRMs. The most serious issue is the inability to adjust the current amplitude to control the rotor angle and achieve a smooth transition to sensorless control. Based on various issues, this article proposes an I-f control method with four stages that can be used in SynRMs. This method uses a simple inductance identification method to solve the flux saturation phenomenon of SynRMs and then uses high-frequency voltage injection to continuously adjust the current amplitude and rotor angle position in conjunction with this inductance identification method. The effectiveness of this method is experimentally demonstrated on a 5.5 kW SynRM.

Two-epoch spectral imagery of the outflow system PV Cep

We continue to study the structure and kinematics of Herbig-Haro (HH) flows. HH flows exhibit a large variety of morphological and kinematical structures. Proper motion (PM) and radial velocity investigations are essential for understanding the physical nature of these structures. We investigated the kinematics and PM of spectrally separated structures in the PV Cep HH flow HH 215. We present observational results we obtained with a 6 m telescope (in Russia) using the SCORPIO multi-mode focal reducer with a scanning Fabry-Perot interferometer. Two epochs of the observations of the PV Cep region in Halpha and SII emission (2003 and 2020-2021) allowed us to study the morphology of the HH 215 jet in detail and to measure the PM and radial velocities for its inner structures. We studied previously known emission knots in the HH 215 flow and new features. Moreover, a newly formed HH knot was revealed. It presumably formed during the large maximum of PV Cep in 1976-1977. We found the high-velocity inner channel in the HH 215 ionized outflow, oriented in the mean direction of the whole HH outflow, and the symmetry axis of the reflection nebula. The position angle of the HH knots located along the axis of the high-velocity channel coincide with its axis (about 325$^ circ $), but others have a completely different value (about 25$^ circ $). This supports the idea that these knots were formed by oblique shocks. We derived a value of i approx 30 for the inclination angle between the flow axis and the line of sight. The total length of the HH 215 outflow probably is about 0.2 pc, and the full length of the bipolar outflow from PV\ Cep (HH 315 + HH 215) can be estimated as 3.6 pc, assuming that the inclination angle is approximately stable.

Investigating Kozai-Lidov oscillations and disc tearing in Be star discs

Abstract Recent simulations of Be stars in misaligned binary systems have revealed that misalignment between the disc and binary orbit can cause the disc to undergo Kozai-Lidov (KL) oscillations or disc-tearing. We build on our previous suite of three-dimensional smoothed particle hydrodynamics simulations of equal-mass systems by simulating eight new misaligned Be star binary systems, with mass-ratios of 0.1 and 0.5, or equal-mass systems with varying viscosity. We find the same phenomena occur as previously for mass ratios of 0.5, while the mass ratio of 0.1 does not cause KL oscillations or disc-tearing for the parameters examined. With increased viscosity in our equal-mass simulations, we show that these phenomena and other oscillations are damped out and do not occur. We also briefly compare two viscosity prescriptions and find they can produce the same qualitative disc evolution. Next, we use the radiative transfer code hdust to predict observable trends of a KL oscillation, and show how the observables oscillate in sync with disc inclination and cause large changes in the polarization position angle. Our models generate highly complex line profiles, including triple-peak profiles that are known to occur in Be stars. The mapping between the SPH simulations and these triple-peak features gives us hints as to where they originate. Finally, we construct interferometric predictions of how a gap in the disc, produced by KL oscillations or disc-tearing, perturbs the visibility versus baseline curve at multiple wavelengths, and can cause large changes to the differential phase profile across an emission line.

ℒ1 adaptive controller of VEGA Launcher subject to flexible modes

Flexible launch vehicle modes contribute to the deterioration of its stability performance. For this reason, their influence must be considered when designing and validating appropriate solutions for its automatic control system. The first three bending modes are the most relevant for control system design and analysis. Next, considerations regarding the elastic modes of the Vega actuator, used in the simulations performed throughout this study, are presented. The IMU (Inertial Measurement Unit) measurements providing attitude angles and angular rates are strongly corrupted by the local elastic deformations resulting from structural flexibility. These measurements are fed back to the TVC (Thrust Vector Control) system which controls the pitch and the yaw motion of the vehicle. The design methodology for this control system is based on an ℒ1 adaptive technique incorporating a Butterworth filter guarantees good stability performances for wide variations of the launcher’s dynamics parameters.

The SARAO MeerKAT galactic plane survey filamentary source catalogue

Abstract We present a catalogue of filamentary structures identified in the SARAO (South African Radio Astronomy Observatory) MeerKAT 1.3 GHz Galactic Plane Survey (SMGPS). We extract 933 filaments across the survey area, 803 of which (${\sim }86~{{\%}}$) are associated with extended radio structures (e.g. supernova remnants and H ii regions), whilst 130 (${\sim }14~{{\%}}$) are largely isolated. We classify filaments as thermal or non-thermal via their associated mid-infrared emission and find 77/130 (${\sim }59~{{\%}}$) of the isolated sources are likely to be non-thermal, and are therefore excellent candidates for the first isolated, non-thermal radio filaments observed outside of the Galactic Centre (GC). Comparing the morphological properties of these non-thermal candidates to the non-thermal filaments observed towards the GC we find the GC filaments are on the whole angularly narrower and shorter than those across the SMGPS, potentially an effect of distance. The SMGPS filaments have flux densities similar to those of the GC, however the distribution of the latter extends to higher flux densities. If the SMGPS filaments were closer than the GC population, it would imply a more energetic population of cosmic ray electrons in the GC. We find the filament position angles in the SMGPS are uniformly distributed, implying that the local magnetic field traced by the filaments does not follow the large-scale Galactic field. Finally, although we have clearly shown that filaments are not unique to the GC, the GC nevertheless has the highest density of filaments in the Milky Way.

Partial Alignment of Astrometric Position Excursions of International Celestial Reference Frame Quasars with Radio Jet Structures

Abstract Published analyses of very long baseline interferometry data for the sources included in the third International Celestial Reference Frame catalog have revealed object-specific, excess astrometric variability and quasi-coherent trajectories as functions of time. A fraction of these sources show markedly elongated distributions of positions on the sky measured with diurnal observations. Here we apply a novel statistical and data-processing method to the diurnal position measurements stretching over 40 yr to quantify the degree of elongation and its position angle, for each source with more than 200 data points. We find that 49% of the examined sources have distribution elongations in excess of 1.3. Robust uncertainties of the directions of maximal astrometric dispersion are computed by the bootstrapping method, and the results are compared with a larger catalog of radio jet directions by A. V. Plavin et al. (2022). Nearly one-half of the sources with smaller position angle uncertainties are found to have astrometric position excursions from their mean positions aligned with the radio jet structures within ±30°.

Association of Scoliosis and Severe Knee Osteoarthritis: A Case-Control Study.

Background/Objectives: Scoliosis has been linked to pelvic position and tilt angle, but few studies have explored its relationship with knee pathology, which can be a significant burden for the elderly. Our aim is to investigate the relationship between scoliosis and knee osteoarthritis (OA). Methods: This population-based case-control study using data from the National Health Insurance Database of Taiwan included patients diagnosed with OA who underwent total knee replacement (TKR) for the first time between 2014 and 2019. Propensity score matching was employed to select controls who did not undergo TKR. Scoliotic cases were identified if they had been diagnosed before knee OA and TKR. The study samples included 10,021 patients with OA/TKR and 30,063 patients without OA/TKR. We then utilized logistic regression analysis to calculate the odds ratio (OR) and 95% confidence interval (CI) for the diagnosis of scoliosis prior to the index date. Results: The findings indicate that patients with pre-existing scoliosis have a 1.627 times greater likelihood of undergoing TKR, with significantly higher odds ratios observed across both female (OR = 1.583) and male (OR = 1.909) and younger (OR = 2.102) and older (OR = 1.575) patients. However, a notable limitation of this study is the absence of data on scoliosis curve side, which prevented us from analyzing the relationship between curve direction and knee arthritis laterality. Furthermore, while we included diagnostic codes indicating left or right TKR, the lack of precise measurements for variables such as lower limb length discrepancies may introduce residual confounding. Conclusions: Our research suggests a significant association between scoliosis and the development of knee OA.

Application of Nonlinear Optimization in Flight Path Reconstruction of a Sub-scale Aircraft

One key challenge in working with free-flight test data is ensuring its compatibility with the dynamic systems of sub-scale unmanned aircraft. This is crucial to avoid errors in measurements, bias, or scaling issues that could compromise the integrity of the estimated results. We refer to this initial processing step as data compatibility checking, a rigorous process that forms the foundation of our research.Typically, this verification process involves flight path data reconstruction (FPR) predicated on estimating the aircraft’s flight kinematics. The predominant methodologies encompass the stochastic approach, the Extended Kalman Filter (EKF), and the deterministic approach, employing the Output Error Method (OEM). In this research, we propose to approach the problem from the perspective of a nonlinear optimizer to estimate the reconstruction of data derived from free-flight tests of a sub-scale aircraft.The nonlinear optimizer we employ in this research was designed to verify the authenticity of the data representing the aircraft's actual flight. It does this by comparing the measurements of attitude angles, accelerations, and velocities with the expected kinematic behavior of the aircraft. This rigorous evaluation process ensures that the reconstructed data is as close to the actual flight as possible, enhancing the reliability of our results.The sub-scale model deployed in these tests was engineered to emulate the dynamic characteristics of a full-scale aircraft, utilizing the Froude number criterion for appropriate scaling. The chosen aircraft for this project was a Cessna 177B, and the sub-scale aircraft was developed by the Aeronautical Systems Laboratory (LSA) at the Aeronautics Institute of Technology (ITA).This study will delineate the outcomes achieved through FPA employing OEM techniques and compare these results with the studies derived from the proposed nonlinear estimation method.

Assessing Reynolds and Jakobsson–Floberg–Olsson models for infinitely long water-lubricated partial journal bearings: Static and dynamic performance predictions compared to computational fluid dynamics analysis

This study evaluates the validity of two numerical models in predicting the performance of infinitely long water-lubricated partial journal bearings (IWLPJB): the non-mass-conserving Reynolds model (RBC) and the mass-conserving Jakobsson–Floberg–Olsson model (JFO). Building upon previous research on inadequately lubricated partial, long water-lubricated bearings, this work employs an efficient modeling approach (EMA) to implement these models, with results compared against computational fluid dynamics (CFD) analysis. A comprehensive evaluation of numerical models under realistic operating conditions is provided, specifically addressing the negative pressure cavitation phenomena of water-lubricated systems. The analysis focuses on conformal surfaces of IWLPJB, examining both static and dynamic performance predictions at the high eccentricity ratios typically encountered in industrial applications. The study examines both untextured and textured cases, assessing bearing performance parameters including maximum hydrodynamic pressure, attitude angle, load-carrying capacity, coefficient of friction (COF), and eight dynamic coefficients. The results indicate that for untextured and partially textured cases, both models provide reliable predictions of the performance parameter values at the studied high eccentricity ratios (0.9–0.98), despite RBC's inaccurate prediction of the cavitation region. Additionally, the differences between the two models are not sensitive to the studied texture depths (7.8–52 μm). For the fully textured case, although prediction errors increased, both models remain applicable for a wide range of performance parameters except for the COF. Notably, this study reveals that the predictive capability of the RBC model for both static and dynamic performance, particularly in textured cases, has been somewhat underestimated in previous research.

SAM: Semi-Active Mechanism for Extensible Continuum Manipulator and Real-Time Hysteresis Compensation Control Algorithm.

Cable-driven continuum manipulators (CDCMs) enable scar-free procedures but face limitations in workspace and control accuracy due to hysteresis. We introduce an extensible CDCM with a semi-active mechanism (SAM) and develop a real-time hysteresis compensation control algorithm using a temporal convolution network (TCN) based on data collected from fiducial markers and RGBD sensing. Performance validation shows the proposed controller significantly reduces hysteresis by up to 69.5% in random trajectory tracking test and approximately 26% in the box pointing task. The SAM mechanism enables access to various lesions without damaging surrounding tissues. The proposed controller with TCN-based compensation effectively predicts hysteresis behaviour and minimises position and joint angle errors in real-time, which has the potential to enhance surgical task performance.

Correlation of anterior CSF space in the cervical spine with Chicago Chiari Outcome Scale score in adult females.

Craniocervical junction morphology has been associated with Chiari malformation type I (CMI) symptom severity; however, little is known about its deterministic effect on surgical outcomes in patients across age and sex differences. The goal of the present study was to assess the effects of age and sex on surgical outcomes in CMI. In the present study, the authors examined MRI-based morphometric data from 115 individuals diagnosed with CMI (54 adults including 39 women and 15 men, and 61 children including 24 girls and 37 boys) and correlated them with Chicago Chiari Outcome Scale (CCOS) scores obtained 1 year after posterior fossa decompression. The authors assessed 7 craniocervical junction morphology-related measures that have been associated with CMI symptom severity: McRae line length, clivus length, Wackenheim angle, anterior and posterior CSF spaces, clivo-supraoccipital angle, and tonsillar position. In the pediatric cohort, none of the morphometric measures correlated with CCOS score, but both anterior and posterior CSF spaces did in adults. To further study sex and age effects, the authors used age group (children vs adults) and sex (female vs male) as independent variables and ran 3 separate ANOVA tests using CCOS score, anterior CSF space, and posterior CSF space as dependent variables, respectively. Both CCOS and anterior CSF space analyses resulted in significant interactions. Specifically, women showed lower CCOS scores and smaller anterior CSF spaces than girls, boys, or men. These results provide evidence that joint age and sex differences moderate the surgical outcome of CMI patients. In females, smaller anterior CSF space was associated with lower CCOS score.